I am surprised by this unexpected event.

This was truly an unexpected result.

When I hear that song, old memories come to mind.

Please teach me how to find the greatest common divisor.

He thought deeply and said, 'I think, therefore I am.'

He strongly believes in the philosophical thought, 'I think, therefore I am.'

He said, 'Where there is a will, there is a way,' and faced the difficult situation.

He always keeps in mind the phrase 'If one learns without thinking, it is a waste.'